1. Formerly Academic Unit of Human Psychopharmacology, Department of Psychological Medicine, Medical College of St Bartholomew's Hospital, London EC1A 7BE, Psychopharmacology Research Unit, Littlemore Hospital, Oxford OX4 4XN, UK
2. Academic Unit of Human Psychopharmacology, Royal London Hospital, St Clements, London E3 4LL
3. Psychopharmacology Research Unit, Littlemore Hospital, Oxford OX4 4XN, UK
4. Formerly Academic Unit of Human Psychopharmacology, Department of Psychological Medicine, Medical College of St Bartholomew's Hospital, London EC1A 7BE, Department of Psychological Medicine, University of Otago, New Zealand